1. Field of the Invention
The present invention relates generally to automotive suspension control modules. More particularly, the present invention relates to an apparatus and method for calibrating an automotive suspension control module to within a preselected tolerance of a predetermined ride height.
2. Disclosure Information
Automotive suspensions employing adjustable suspension units typically utilize one or more sensors for detecting the position of one or more portions of the suspension with respect to either another part of the suspension itself or another part of the chassis of the vehicle. In the case of vehicles using load leveling, air, hydropneumatic or hydraulic suspension systems, it is necessary to know the ride height of the vehicle in order to determine whether correction of the ride height is required. In the event, for example, that the ride height is less than prescribed limits, as determined by the height sensor, an adjustable suspension unit may be given the command to increase the ride height. Conversely, in the event that the ride height exceeds the prescribed limits, the adjustable suspension unit may be given the command to lower or decrease the ride height.
Various vehicle height control systems have been proposed including means for maintaining optimal performance of the suspension system. For example, U.S. Pat. No. 4,517,832, assigned to the assignee of the present invention, discloses a method of diagnosing an air suspension system for possible faults within the system. The patent discloses the steps of energizing the air suspension units to the fully extended or rebound position and reading the output signals of the height sensors at that point to check whether the output signal corresponds correctly to the rebound position. The patent further discloses similar steps in checking the height sensor output signal when the air suspension unit is fully deflated as well as at a predetermined trim height. However, the patent does not teach any method for calibrating the vehicle suspension control module in the event that the height sensor output signal does not correctly correspond to the actual ride height of the vehicle. With the advent of analog height sensors which measure the distance between the sprung and unsprung mass of the vehicle in continuous increments, it is especially important that the suspension control module be calibrated to correspond the sensor output signal to the actual ride height of the vehicle.
It is an object of the present invention to provide an apparatus for calibrating a suspension control module which may be utilized in a factory setting in a cost and time efficient manner.
It as an advantage of the present invention that the suspension control module and height sensors may be calibrated without the need for lock-in-place brackets or other tooling.
These and other objects, features and advantages of the present invention will become apparent from the summary, drawings, detailed description and claims which follow.